MLH1 and hereditary nonpolyposis colon cancer: However, it is now increasingly used for adult-onset conditions, including hereditary cancer predisposition syndromes such as hereditary breast and ovarian cancer syndrome (i.e., germline BRCA1/BRCA2 variants) and Lynch syndrome (previously known as Hereditary Non-Polyposis Colorectal Cancer/HNPCC due to germline MLH1, MSH2, MSH6, PMS2, or EPCAM variants) [9].